APA (7th ed.) Citation

Brown, D., Cohen, D., & O'Day, J. (1991). Challenges: A process approach to acadenic english. Prentice Hall.

Chicago Style (17th ed.) Citation

Brown, D., D. Cohen, and J. O'Day. Challenges: A Process Approach to Acadenic English. New Jersey: Prentice Hall, 1991.

MLA (8th ed.) Citation

Brown, D., et al. Challenges: A Process Approach to Acadenic English. Prentice Hall, 1991.